(a) Field of the Invention
The present invention relates to an electrolyte for a rechargeable lithium battery and a rechargeable lithium battery including the same. More particularly, the present invention relates to an electrolyte for a rechargeable lithium battery having excellent thermal stability and ion conductivity, and a rechargeable lithium battery including the same.
(b) Description of the Related Art
Conventional rechargeable lithium batteries have used a mixed electrolyte including cyclic esters such as ethylene carbonate, propylene carbonate, and so on, linear esters such as dimethyl carbonate, ethyl propionate, and so on, and cyclic ethers such as tetrahydrofuran. However, the linear esters or cyclic ethers have a low flash point, and therefore the conventional electrolyte including the linear esters or cyclic ethers in a large volume % has a problem of low thermal stability. Japanese Patent laid-open Nos. 1996-78053, 1999-214032, and 2000-58123 discloses a silicone oil as a solvent to provide a thermally stable and environmentally-friendly electrolyte.
The silicone oil used in the electrolytes disclosed in the Japanese Patent laid-open Nos. 1996-78053, 1999-214032, and 2000-58123 has good thermal stability, but a rechargeable lithium battery using the electrolyte has insufficient ion conductivity.